Valved sheath introducer for venous cannulation

ABSTRACT

A valved sheath introducer for venous cannulation, including a valve, sheath, handle and cap. The valve is configured to permit safe introduction and removal of medical instruments through the sheath introducer. The valve may have one or more anchoring members and a thickened central portion through which a slit is formed. The central portion may have one or more concave surfaces and the slit can be angled with respect to the top surface of the valve. The cap is attached to the handle, compressing a portion of the valve therebetween.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/119,599, filed May 2, 2005, now U.S. Pat. No. 7,637,893, which claimsthe benefit of U.S. Provisional Application No. 60/566,896, filed Apr.30, 2004, each of which is expressly incorporated by reference as iffully set forth herein.

BACKGROUND OF THE INVENTION

Introducer devices are commonly utilized for inserting medical devices,such as venous access catheters, into patients. Typically, suchintroducer devices comprise a peel-away sheath and a hub/handle assemblywhich is used in conjunction with a dilator assembly to access the veinof a patient, following insertion of a needle and guidewire. Inparticular, procedures for introducing a catheter into a blood vesselinclude the cut-down method and the Seldinger technique. The Seldingertechnique involves first inserting a needle through the skin of apatient and into a vein to be catheterized, inserting a guidewirethrough the needle and into the vein, removing the needle from theguidewire and inserting the dilator and introducer sheath over theguidewire and into the vein, simultaneously removing the dilator andguidewire from the introducer sheath, inserting a catheter through theintroducer sheath and into position within the accessed vein. Followinginsertion of the catheter, the introducer sheaths are generally designedsuch that they can be peeled away from the catheter, without affectingthe catheter positioning within the vein. Such introducer sheaths andassemblies are described, for example, in U.S. Pat. No. 4,772,266 toGroshong, issued Sep. 20, 1988, and U.S. Pat. No. 4,306,562 to Osborne,issued Dec. 21, 1981, each of which is incorporated by reference herein.

Problems, however, with the above-described procedure include, 1) thatupon removal of the dilator and guidewire from the sheath, blood lossthrough the sheath can occur, and 2) that the introducer sheath providesa conduit for the introduction of air into the patient's vein, which canresult in air embolism. Moreover, the risk of air embolism increases inproportion to the diameter size of the indwelling sheath, meaning thatlarger diameter sheaths routinely used for the placement of largerdiameter catheters would increase such risk. Thus, there have been avariety of solutions proposed, which involve the incorporation of avalve in the proximal end of the introducer sheath, which would allowpassage of a guidewire and dilator while simultaneously preventing bloodloss or the introduction of air through the sheath. Such proposedsolutions can be found, for example, in U.S. Pat. No. 5,125,904 to Lee,issued Jun. 30, 1992, U.S. Pat. No. 5,397,311 to Walker et al., issuedMar. 14, 1995, U.S. Pat. No. 6,083,207 to Heck, issued Jul. 4, 2000,each of which is incorporated by reference herein.

The aforementioned and similarly directed patents are concernedprimarily with providing an elastic valve structure that provideshemostasis and the prevention of blood loss or bleed back for arterialcannulation procedures where there is significant positive bloodpressure. On the other hand, with respect to venous cannulation, bloodpressure is much lower and negative pressures may be involved, meaningthat while prevention of blood loss is an ancillary concern, it is theprevention of air embolism that is the most crucial consideration. Thus,there exists the need for a valved sheath introducer designed forparticular use for venous cannulation.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a valved sheathintroducer for venous cannulation. In one embodiment of the invention,the valve in the introducer includes a thin disk with a central slit andincludes features such as opposing anchors to allow stretching of thedisk when a medical device is inserted therethrough, a thickened centralportion through which a self-sealing slit is positioned, which promotesoptimal resealing upon removal of a medical device, and mechanical orother means of splitting the disk simultaneous to the breaking andseparating of a sheath handle from an inserted medical device. In oneembodiment, the thickened central portion or island has a concavesurface. Some embodiments of the valve include slits or notches alignedwith the central slit to facilitate separation of the valve when thesheath and handle are removed from an inserted medical device.

In another embodiment of the invention, an apparatus for insertion of amedical device into a body comprises a sheath comprising a sheath bodyand a handle, the handle including at least one receiving section, avalve comprising a slit through a central portion thereof and at leastone anchoring member configured for insertion into the handle receivingsection, the anchoring member being positioned along an edge of thevalve, and a cap attached to the handle, at least a portion of the valvebeing compressed therebetween. In another embodiment, a wire is loopedthrough a slit positioned in the valve, such that when the handle isseparated and removed from medical device inserted through the valvedsheath introducer, the wire cuts the valve into two portions.

In one aspect of the valved sheath introducer, the valve is designed toprovide optimal sealing when removing an instrument, such as a dilator.The optimal sealing occurs due to the configuration of the valve, suchas a central portion or island and one or more anchoring members, andthe way in which the valve is tightly held between a handle and a cap.Thus, upon removal of an instrument from the introducer sheath, thevalve body, which is stretched as the instrument is insertedtherethrough, rebounds toward the handle but cannot resume its originalposition due to the pressure exerted by the cap and the handle. Theresult is a bunching or duckbill effect of the valve that provides adesirable seal.

These and other embodiments, features and advantages of the presentinvention will become more apparent to those skilled in the art whentaken with reference to the following more detailed description of theinvention in conjunction with the accompanying drawings that are firstbriefly described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side perspective view of one embodiment of a valvedsheath introducer with an inserted dilator.

FIG. 2 illustrates a side perspective view of the sheath introducer ofFIG. 1 in isolation.

FIG. 3 illustrates a top view of the handle of the sheath introducer ofFIG. 2.

FIG. 4 illustrates a bottom view of one embodiment of a valve for avalved sheath introducer.

FIG. 5 illustrates a side view of the valve of FIG. 4.

FIGS. 6A and 6B illustrate a cross-sectional view of the valve of FIG.4.

FIG. 7 illustrates a bottom view of another embodiment of a valve for avalved sheath introducer.

FIG. 8 illustrates a bottom view of yet another embodiment of a valvefor a valved sheath introducer.

FIGS. 9A-9D illustrates an advantageous feature of one embodiment of avalve for a valved sheath introducer.

FIG. 10 depicts an alternate embodiment of a valve for a valved sheathintroducer along with a handle and cap prior to assembly.

FIG. 11 depicts the valve of FIG. 10 in isolation with the handle.

FIG. 12 is a cross-sectional assembled view of the cap, handle and valveof FIG. 10.

FIG. 13 is a further cross-sectional view of the cap, handle and valveof FIG. 12.

FIG. 14 is an alternate embodiment of a valve with an island, the islandhaving a concave surface.

FIG. 15 is a cross-sectional view of the valve of FIG. 14.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description should be read with reference to thedrawings, in which like elements in different drawings are identicallynumbered. The drawings, which are not necessarily to scale, depictselected embodiments and are not intended to limit the scope of theinvention. The detailed description illustrates by way of example, notby way of limitation, the principles of the invention. This descriptionwill clearly enable one skilled in the art to make and use theinvention, and describes several embodiments, adaptations, variations,alternatives and uses of the invention, including what is presentlybelieved to be the best mode of carrying out the invention.

The present invention involves valves and valved sheath introducers usedparticularly in venous cannulation procedures. However, it should beappreciated that while the designs described herein are intended forsuch use, they may be equally suitable for a variety of other uses(e.g., arterial cannulation, introduction of pacing leads, etc.) andtherefore should not be so limited. Further, while sheath introducersand sheath introducer assemblies are described herein for exemplarypurposes of housing and implementation of the subject valves, it shouldbe appreciated that many different configurations and types of sheathintroducers and sheath introducer assemblies would be equally suitablefor use with the valves of the present invention and therefore should inno way serve to limit the scope of the valves described herein. Inaddition, as used in this specification and the appended claims, thesingular forms “a,” “an” and “the” include plural referents unless thecontext clearly dictates otherwise. Thus, for example, the term “a slit”is intended to mean a single slit or more than one slit.

Referring now to FIGS. 1 and 2, a valved sheath introducer assembly 10according to one embodiment is shown, including a valved sheathintroducer 20 and a dilator 50. The valved sheath introducer assembly 10is shown in its insertion configuration with dilator 50 insertedcompletely through the valved sheath introducer 20 and locked thereto.The valved sheath introducer 20 includes a sheath body 22, a handle 30,a cap 40, and an internal valve 100 (FIG. 4). In this embodiment, thehandle 30 has a first side 32 and a second side 34 separated by twoslots 36, positioned approximately 180° apart. The sheath body 22 has atapered distal end 24 to facilitate insertion into a blood vessel. Inone embodiment, the sheath body 22 is made of polytetrafluoroethylene(PTFE) and the handle 30 and cap 40 are made of K-Resin®(styrene-butadiene copolymer). In another embodiment, the handle 30 andcap 40 are made of Cryolite® (poly(methyl methacrylate)). Of course,other materials are also possible for the sheath body, handle and cap,including other polymer materials (e.g., polycarbonate, thermoplastics,etc.), as is apparent to one of ordinary skill in the art.

In an exemplary manufacturing process for the valved sheath introducer20, the handle 30 is insert molded over the proximal end 26 of thesheath body 22. After molding, the valve 100 is placed on the top of thehandle 30, and the cap 40 is attached to the handle 30 (e.g., viaultrasonic weld, adhesives, screws, etc.) over the valve 100 underforce. In one exemplary manufacturing method, the attachment method isultrasonic welding wherein the sheath body 22 and handle 30 are placedinto an ultrasonic welder and the cap 40 is pressed onto the handle 30after the valve 100 has been set therein. The ultrasonic welder sendsvibrations through the cap 40, causing a portion of the cap 40 andhandle 30 to meld together. In one embodiment, the cap 40 is in two partform prior to welding such that a small gap in alignment with the slots36 can be provided. In a top view of the handle 30, shown in FIG. 3prior to attachment of the valve 100 and cap 40, slots 36 can be seen inmore detail as can the handle bore 39, which is configured to beapproximately the same diameter as that of the lumen of the valvedsheath introducer 20. In addition, valve receiving sections 38 can beseen configured to accommodate valve anchors 102, 104 (FIG. 4), as willbe explained in more detail below.

Referring back to FIG. 1, the dilator 50 includes a threaded luerconnector 52, which rotates independently of the dilator body 56, and isconfigured for mating with the cap 40 to lock the dilator 50 to thevalved sheath introducer 20. The body 56 has a diameter approximatelyequal to that of the lumen of the valved sheath introducer 20 and alsohas a tapered distal end 58 to provide ease of insertion of the valvedsheath introducer assembly 10 into a blood vessel. The dilator 50 alsoincludes a luer connection 54 at the proximal end thereof for attachmentto devices used for purposes such as flushing. An injection cap (notshown) may also be placed over the proximal end of the dilator.

FIGS. 4-6B illustrate one embodiment of a valve 100 for incorporationinto a valved sheath introducer. FIG. 4 is a bottom view of valve 100,which is a thin disk-like body 108, including valve anchors 102, 104around the circumferential edge of the body 108 and disposed on the backside thereof. The valve anchors 102, 104 extend from the body 108, ascan be seen in FIGS. 5 and 6A, and are configured in size and shape tocorrespond with the valve receiving sections 38 of the handle 30 (FIG.3) to ensure that the valve 100 remains in axial position as instrumentsare inserted therethrough and withdrawn therefrom, and also to ensurethat the valve 100 properly separates (each side of the valve remainingwith its respective side of the handle into which it is held) uponremoval of the sheath introducer 20 from an inserted instrument.

FIG. 6A is a cross-section of the valve of FIG. 4 taken along line6A-6A, showing the relative thickness of the island 106 compared to theopposing anchors 102, 104. As shown in this embodiment, the islandthickness is slightly less than that of the anchors, although in otherembodiments, the island thickness is either the same or greater than thethickness of the anchors. In still other embodiments, the anchors 102,104 have different thicknesses, each of which may be greater than, lessthan or equal to the island thickness. Also, in the embodiments shown,the anchors 102, 104 have rounded edges 116, although otherconfigurations, including edges with opposing right angles, arecertainly contemplated herein. FIG. 6B illustrates another embodiment ofthe valve 100, including a slit 110A that is cut through the middleregion of the valve 100, traversing at an angle from a top surface ofthe valve to a bottom surface thereof (e.g., to a surface of the island106) that is different from the approximately 90° angle with respect tothe top surface of the valve shown in FIG. 6A. While the slit 110A isshown as cut at approximately a 45° angle, certainly any othernon-parallel angle with respect to the top surface of the valve ispossible as should be appreciated by one of ordinary skill in the art.

The anchors 102, 104 allow for a tight tolerance with respect to thepositioning of the valve 100 within the handle 30, being tightly securedtherein by the cap 40, as explained above. This tight tolerance resultsin an advantageous reaction by the valve 100 with respect to sealingthereof upon removal of an instrument that had previously been insertedtherethrough (e.g., dilator, etc.). In particular, in concert with theisland 106, which is a circular feature positioned in the center of thebody 108, extending along with the anchors 102, 104 from the bottomthereof, a superior seal is created upon removal of an instrument fromthe sheath introducer 20, as will be explained below in connection withFIGS. 9A-9D. It should be appreciated that while the valve 100 has acircular shape and the valve anchors 102, 104 have a semi-circularshape, as seen in FIG. 4, various shapes and sizes are possible andcontemplated herein to correspond with the shape and size of the handleand receiving sections onto/into which they are positioned.

In the embodiment shown in FIG. 4, approximately equidistantly spaced onthe edge of the body 108 between the valve anchors 102, 104 on oppositesides of the body 108 are peripheral slits 112, 114, which enable thevalve 100 to be easily split in half along the line extending from slit112 to slit 114. These slits can also be in the form of notches havingvarious shapes, two of which (122, 124 and 132, 134) are illustrated inFIGS. 7 and 8. While the notches shown are in the shapes of trianglesand trapezoids, other shapes are possible and are contemplated herein tofacilitate the separation of the valve 100. A central slit 110 throughwhich instruments can be inserted is cut through the valve body 108 andisland 106 and is positioned approximately centrally with respect to theedges of the valve 100. While only one slit is shown, in otherembodiments two or more slits are formed through the valve in differentpatterns. For instance, in one embodiment, multiple slits are cutthrough the valve in a pattern similar to an asterisk when viewed fromthe top or bottom thereof. As discussed, when the valve 100 is placedinto the handle 30, the valve anchors 102, 104 are positioned inreceiving sections 38 of the handle 30, which places the island 106within the opening of the handle bore 39. Such alignment results in theslits 112, 114 being aligned with the slots 36 of the handle 30.

The following materials and dimensions are provided as an example of oneembodiment and should not be taken as limiting the invention in any way.The valve 100 in this embodiment is made of silicone (Dow CorningQ7-4840), having a diameter of approximately 0.516 inches, while thediameter of the island 106 is approximately 0.260 inches and thedistance between inner edges of the islands 102, 104 is approximately0.420 inches (the width of the anchors thus being approximately 0.048inches). The thickness of the valve 100 along the anchors 102, 104 isapproximately 0.090 inches, while the thickness of the valve across theisland is approximately 0.045 inches, the remainder of the bodytherefore having a thickness of approximately 0.025 inches. The distancebetween the anchors 102, 104 is approximately 0.160 inches on both sidesof the valve 100. The central slit 110 has a length of approximately0.204 inches, while the peripheral slits 112, 114 have a length ofapproximately 0.050 inches. In other embodiments, the dimensions aredependent upon the size of the instrument(s) being inserted through thevalve.

With respect to the valve island 106, another embodiment is shown inFIGS. 14 and 15. Valve 300 is shown, including one or more anchors 302and an island 306 that has a concave surface 304 extending into thethickness of the valve body 308 and a slit 310. The slit 310 as shown ispositioned at an angle of approximately 60° with respect to the topsurface of the valve, although as stated above in connection with FIGS.6A and 6B, any other non-parallel angle with respect to the top surfaceof the valve is possible. The curvature of the concave surface can bemore or less than shown and can extend short of, or up to, the line ofthe valve body in other embodiments. The depth of the concavity is alsovariable, which alters the thickness of the mid-point of the island indifferent embodiments. As shown in FIG. 15, the edges of the island arecurved, although as with the anchors, other types of edges are possible.Numerous embodiments are contemplated with respect to the configurationof the island and slits or notches in the valve. For instance, the valvecould have a concave surface on the island along with notches onopposing sides of the valve, the valve could have a concave surface onthe island and an opposing concave surface on the top of the valve withno slits or notches, the valve could have notches or slits but noisland, etc.

FIGS. 9A-9C depict the configuration of one side of the valve 100 withrespect to the handle 30 and the cap 40 as an instrument is insertedtherethrough (FIG. 9B) and withdrawn therefrom (FIG. 9C). An imaginarygrid is provided to aid in the illustration of the movement andpositioning of the valve 100 with respect to the handle 30 and the cap40. It should be appreciated, however, that the grid is exemplary onlyand isn't intended to depict actual distances or precise intervals. InFIG. 9A, the valve 100 is tightly held between the handle and the capprior to insertion of an instrument therethrough. Close inspection ofthe valve 100 reveals that the thickness of the valve material 150between the handle 30 and the cap 40 is slightly less than the thicknessof the valve material 160 outside of this area (i.e., within the handlebore 39). This is due to the pressure exerted onto the valve 100 as thecap 40 is attached to the handle 30 as explained above. As can be seen,the distance between the marks on the grid line in FIG. 9A are the samefor both valve material 150 and 160.

FIG. 9B depicts the movement of the valve 100 upon insertion of aninstrument therethrough, the valve material 160 stretching andexperiencing a reduction in thickness such that the thickness thereof isapproximately equivalent to the thickness of valve material 150(although certainly the thickness of the valve material 160 could begreater than or equal to the valve material 150 as it is stretched uponinsertion of an instrument through valve 100). In addition to thethickness of the valve, this demonstration of stretching is evidenced bythe increased distance between the marks on the grid line along valvematerial 160. Although the valve material 150 is still held tightlybetween the cap 40 and the handle 30 while an instrument is insertedthrough the valve 100, stretching of the material does occur. Thisaction is revealed in FIG. 9B by the grid line as the distance betweenthe marks on the grid line is shown to increase. It is noted here thatwhile the material adjacent to the anchors stretches slightly uponinsertion of an instrument through the valve 100, the anchors themselvesremain in position inside the receiving sections of the handle.

FIG. 9C depicts the valve 100 upon removal of the inserted instrument,at which point the valve material 150 and 160 rebounds back toward theside of the handle 30. However, because the valve material 150 istightly held between the cap 40 and the handle 30, a bunching effectoccurs as stretched valve material 150 that has moved from an originalposition between the handle 30 and cap 40 toward the center of thevalved introducer 20 is prevented from returning to its originalposition. This phenomenon is illustrated by the grid line in FIG. 9C,which shows the distance between marks in valve material 150 to beapproximately the same as the distance in FIG. 9B, whereas the distancebetween marks in valve material 160 has slightly decreased. Thisbunching effect leads to a duckbill-like configuration for the valve 100as shown in FIG. 9D, which illustrates the configuration of the centralregion of the valve following removal of an instrument. Such aconfiguration provides a superior seal over the valves of the prior art.In one embodiment, the valve 100 is provided with a lubricant in orderto ease the surface friction between the valve and inserted instrument,thus maintaining the desired duckbill shape.

Removal of the sheath introducer 20 from an instrument insertedtherethrough (e.g., a catheter) is effectuated by grasping the handle 30on each side thereof and pulling the sides in opposite directions sothat the handle 30 cracks along the slots 36. Upon cracking andsplitting of the handle 30, the integrated valve 100 tears along theslit line created by central slit 110 and peripheral slits 112, 114, thetearing process enabled, as discussed above, by the anchors 102, 104,which maintain the position of each side of the valve 100 within therespective side of the handle. As the two pieces of the handle arepulled away from one another, the sheath peels down its entire length atthe circumferential location of the handle slots (which correspond tothe aligned pre-split sections of the sheath). Due to the extrusionprocess for manufacturing the PTFE, which results in an alignment of themolecules, the peeling of the sheath is continuous down the entirelength thereof at the circumferential locations without the need forscore line(s). The handle does not detach from the sheath during orafter the splitting process. In other embodiments of the invention, thesheath is made from PTFE or another like polymer material with one ormore score lines positioned longitudinally along the length of thesheath in line with the slot(s) in the handle.

In another embodiment of a valved sheath introducer, a very thin wire isassociated with the valve, as shown in FIGS. 10-13. FIG. 10 illustratesa handle 230, a cap 240 and a valve 200, which includes a single anchor202 and a thin wire 204, prior to assembly. The wire 204 is loopedthrough the central slit of the valve 200 and each end extends beyondthe edge of the valve 200, being coupled together for positioning in thehandle 230. The central slit of valve 200 is oriented perpendicular tothe slots of the handle 230, differently than the axial alignment ofvalve 100 described above. It should be noted that in this view, the cap240 has an extension pattern 242 configured to be received within a likeshaped extension pattern in the handle 230 for an improved connectiontherebetween. FIG. 11 illustrates the valve 200 placed into the handle30. FIG. 12 illustrates the interaction of the handle 230, cap 240 andvalve 200 by showing a cutaway view of the cap 240 and handle 230 with atop perspective view of the valve, while FIG. 13 shows another cutawayview of the handle 230 and cap 240 with a cross-sectional view of thevalve 200 also being shown.

In FIG. 13, the side of the handle 230 that receives the wire 204 can beseen to also have an empty receiving section 238 due to the fact thatthe valve 200 does not contain an anchor for positioning therein. Whilein some embodiments, this empty section does not exist, in thisparticular embodiment the presence of receiving sections in both sidesof the handle 230 facilitates manufacture of the valved sheathintroducer by permitting positioning of the anchor 202 in either side ofthe handle. When the handle 230 is broken to remove from an insertedinstrument (e.g., a catheter), the wire 204 remains with the half of thehandle 230 into which the extension thereof has been set (FIG. 11),while the valve 200 remains with the opposite half, into which theanchor 202 is set (FIGS. 12, 13). Thus, as the halves of the handle 230are pulled in opposite directions, the wire 202 cuts the valve 200,slicing it into two parts for easy removal from the inserted instrument.

The valved sheath introducer described herein is used according to oneembodiment as follows. After an access site on a body is determined andan incision made, the valved sheath introducer assembly is inserted intothe body with a distal end of the sheath body extending into a bodyvessel to be accessed. Following optional preparatory steps (e.g.,flushing), the dilator is removed from the valved sheath introducer. Asthe dilator is removed, the valve closes as described above inconnection with FIGS. 9A-9C. A catheter or other medical device can thenbe inserted through the valved sheath introducer and into the bodyvessel. When the desired positioning of a more permanent medical device,such as a catheter, has been accomplished, the valved sheath introduceris ready to be removed. In one embodiment, the handle is cracked bypulling a first side and a second side of the handle in oppositedirections (i.e., away from the inserted medical device). This crackingaction may take place, for example, along slots positioned in the handlebetween the first and second sides. By pulling the handle apart, thevalve is separated such that one portion remains with the first side ofthe handle and another portion remains with the second side of thehandle, as is described in exemplary embodiments herein. Once the handleis broken and the first and second sides are continued to be pulled inapproximately opposite directions away from the inserted medical device,the sheath body is torn down its length so that complete removal of thevalved sheath introducer from around the inserted medical device ispossible without affecting the positioning of the medical device in thebody vessel.

This invention has been described and specific examples of the inventionhave been portrayed. While the invention has been described in terms ofparticular variations and illustrative figures, those of ordinary skillin the art will recognize that the invention is not limited to thevariations or figures described. In addition, where methods and stepsdescribed above indicate certain events occurring in certain order,those of ordinary skill in the art will recognize that the ordering ofcertain steps may be modified and that such modifications are inaccordance with the variations of the invention. Additionally, certainof the steps may be performed concurrently in a parallel process whenpossible, as well as performed sequentially as described above.Therefore, to the extent there are variations of the invention, whichare within the spirit of the disclosure or equivalent to the inventionsfound in the claims, it is the intent that this patent covers thosevariations as well. Finally, all publications and patent applicationscited in this specification are herein incorporated by reference intheir entirety as if each individual publication or patent applicationwere specifically and individually put forth herein.

1. A method for assembling a valved sheath introducer, comprising:providing a valve including a slit, the valve comprising at least oneanchoring member and a central portion, the slit traversing through thecentral portion; inserting the valve into a handle, the anchoring memberpositioned in a receiving section of the handle and the central portionpositioned in a bore of the handle, the central portion having adiameter approximately equal to a diameter of the bore, the anchoringmember and central portion extending distally into the handle; andattaching a cap to the handle under pressure, the cap contacting aproximal most surface of the valve and compressing the valve between thecap and the handle.
 2. The method according to claim 1, wherein theproviding step further comprises providing the central portion of thevalve with a thickness less than a thickness of the anchoring member. 3.The method according to claim 2, wherein the providing step furthercomprises providing the central portion of the valve with a concavesurface.
 4. The method according to claim 3, wherein the providing stepfurther comprises providing the slit of the valve at an angle ofapproximately 60 degrees with respect to the proximal most surface ofthe valve.
 5. The method according to claim 1, wherein the providingstep further comprises providing the valve with a first anchoring memberand second anchoring member, the inserting step further comprisingpositioning the first anchoring member in a first receiving section in afirst side of the handle and positioning the second anchoring member ina second side of the handle opposite from the first side of the handle.6. The method according to claim 5, wherein the providing step furthercomprises providing the central portion of the valve with a thicknessless than a thickness of the first and second anchoring members.
 7. Themethod according to claim 1, wherein the attaching step furthercomprises ultrasonically welding the cap to the handle.
 8. The methodaccording to claim 1, wherein the attaching step further comprisesattaching a first part of the cap to a first side of the handle andattaching a second part of the cap to a second side of the handle suchthat a gap between the first and second parts of the cap is aligned withone or more slots in the handle.
 9. The method according to claim 1,wherein the providing step further comprises providing the slit of thevalve at an angle of approximately 45 degrees with respect to theproximal most surface of the valve.
 10. The method according to claim 1,wherein the providing step further comprises providing the valve with aperipheral slit positioned at an edge of the valve, the peripheral slitaligned with the slit through the central portion.
 11. The methodaccording to claim 1, wherein the providing step further comprisesproviding the valve with two peripheral slits positioned at opposingedges of the valve, the peripheral slits aligned with the slit throughthe central portion.
 12. The method according to claim 1, wherein theproviding step further comprises providing the valve with two peripheralnotches positioned at opposing edges of the valve, the peripheralnotches aligned with the slit through the central portion.
 13. Themethod according to claim 1, wherein the providing step furthercomprises providing the valve with a wire that is looped through theslit, the wire having free ends thereof positioned in the handle.